Resolves positively if Elon Musk publicly declares (via his own twitter account, on a Neuralink demo presentation, or credible media that he explictly confirms to be accurate) that he's had any kind of BCI/BMI (brain-computer interface/brain-machine interface) installed on himself as augmentation and not as a way to treat a health condition (similar criteria to this question on metaculus, but narrowed down to an implant intended to allow him to deliberately interact with devices outside his own body).
@CollectedOverSpread good question. Yeah, I'm interested in the narrower case of an invasive neural interface that he can use to interact with devices outside his own body.
So if he gets an implant, for instance, to augment attention/memory/baseline happiness or whatever that passively does its work in a closed loop between his brain and the system (even if part of the loop includes processing outside his brain, but nothing he directly and willingly controls with his mind) it doesn't count.
Invasive is also important. If he attaches something under the skin but nothing physically goes inside his brain, it doesn't count.
I like the part in the Metaculus question about it not having to work. Something gets physically inserted into his brain with the intention of allowing deliberate interaction with external devices, but it fails. That would still count.